Means for controlling the injection-air of combustion-engines.



J. MULLB MEANS FOR CONTROLLING THE INJECTION AIR 0F GOMBUSTION ENGINES.

APPLICATION FILED APR.30,1913.

LILQG ESEL a Patented F6112, 1915.

WITNESSES IIW/EA/TUI? Z Zw f N Li a By AY, LN ATTORNEYS neer, a citizenof the Republic @FTQE JAKOB M'ULLER, 0F WINTERTHUR, SWITZERLAND,ASSIGNOR T0 BUSCH-SULZER BROS.- DIESEL ENGINE COMPANY, OF ST. LOUIS,MISSOURI, A CORPORATION OF MISSOURI.

1!['.lilAI\'l'S FOR CONTROLLING THE INJECTION-AIR 0FGOIVIBUS'1ION-IElNGINE ar ssa.

Specification of Letters Patent. 7

Application filed April 80, 1918. Serial Ito. 764,499.

To all whom it may concern Be it known that I, J AKOB Mt'ILLnR, engiofSwitzerland, residing at Winterthur, Canton of Zurich, Switzerland, haveinvented the following described new and useful Improvemerits in Meansfor Controlling the Tnjection-Air of Combustion-Engines.

This invention relates to the regulation of internal combustion enginesof the kind in which the fuel is injected in atomized forminto thecylinders by air under relatively high pressure, as, for example, Dieseltype engines in which the fuel is thus in troduced partly or whollyduring a part of the working stroke into a body of air previously highlycompressed in the cylinder to a temperature sufficient to produceignition. Regulation of the output of such engines, either to compensatefor load variations or to change the speed, is effected in various ways,among them by varying the pressure of the fuel injection air; and theobject of the present invention-is to provide simple and eifective meansfor securing prompter regulation of this factor at the point of injection than has customarily been attained. According to a commonpractice the injection air pressure is increased or decreased byvariably throttling the intake of the multistage air compressor drivenby the engine, thus altering the quantity supplied by the high pressurestage of such compressor to the injection air line; but under suchconditions, and particularly when receivers and cooling provisions areinterposed between the stages of the pump or between the latter and thefuel valve, or both, the response in the line immediately to said valveis comparatively sluggish, so that the sensitiveness of control which isdesirable or necessary when operating under frequently or suddenlyvarying load conditions is not obtainable.

The application of Paul G, Roesti, Serial No. 700,948, filed June 1,1912, discloses a construction whereby the; prompt variation in pressurein'a low pressure stage 01:' the compressor or even in the suction linethereoffproduced as heretofore by throttling the intake more or less,eithe'r manually or'automatically, is utili'zedto vary the pressure inthe injection line in a corresponding manner and with substantiallyequal promptitude dicated by dotted lines at 70.

through suitable connections controlling a throttling device in the saidline. In this way not only is the pressure of the injection air variedin the high pressure line in a con venient and practical manner, but adual control is provided which is particularly effective in securingsensitive and exact regulation.

The present invention relates to certain improvements in such apparatus.

The accompanying drawing illustrates an embodiment of the invention,parts being shown in section and parts in elevation, and no attemptbeing made to show the throttling and control devices for the highpressure line in scaleproportional to theengine.

The drawing represents an ordinary Die-- sel engine at, either two cycleor four cycle, having a usual form of atomizing fuel valve 6, with aconnection 8 to the oil supply and a connection to the high pressure airline i. The internal construction of such valves is well known and istherefore not illustrated. The engine is further provided with a usualor suitable automatic governor g, which, in

addition to controlling the air pressure as hereinafter described, mayalso vary the valve lift, that is to sav the duration of fuel admission,in the well known manner by eccentrically shifting the fulcrum of thevalve lifting lever t.

A usual form of two stage air compressor driven by the engine isindicated at 0, cl, The construction of such multistage compressors isfamiliar to those skilled in the art and requires no particularillustration or description here. The suction line or intake for thefirst or low pressure stage a will be recognized at e, and it will beunderstood that the air passes from one stage to another in the usualmanner and that the usual cooling and receiver provisions may beinterposed between the stages. From the high pressure stage extends theinjection air line a", and receivers and cooling provisions may also beprovided therein, a receiver being in- Obviously the compressor mighthave more than two stages, and if the engine operates on a two strokecycle, air from a low pressure stage Wlll be used for scavenging as iscustomary.

' In the pump intake e is a su1table or usual form of throttle valve,such as indicated at f, and this valve may be operated either PatentedFeb, a, rats, i

manually orautomatically, or in bothways. Automatic control is indicatedby linkage h from the stem of the governor g. By con-- motions of thisor other appropriate 'character the amount of air drawn in by the pumpisv regulated in proportion to the variations of engine load, and inconsequence of this intake throttling there is a substantially immediatechange of pressure in the lower stage or stages of the compressor, butunder ordinary conditions it would take air appreciable length of timefor the eflect to reach the portion of the high pressure line leadingdirectly to the fuel valve. This defeet is remedied in the presentinvention as by it may be liftedmore or less-away from and a piston'm',which is thus subjected to its seat, in opposition to a spring at toseat the valve. The part m is a pneumatic device or motor-mechanicallyconnected with the valve Z on the one hand and in communication with alow pressure stage of the pump on the other. Its construction may ofcourse bevaried, but as shown somewhat diagrammatically in the drawingit comprises a cylinder, connected by a pipe 0 with the pump,

the varying pressure effects in the pump corresponding to the setting ofthe throttle f. The movement; of the piston in one direction can becontrolled by a spring p or in. any usual way, this representation ofthe regulating motor. being merely representative of any suitable typeof similar device, and it will be understood that in practice anysuitable provisions may be applied to it for increasing the positivenessand steadiness of its action, such, for example, as the addition ofdash-pot agencies for determining definite rates and limits of thepistons movement. The pipe 0, it will be understood, connects with thelow pressure sta e of the pump, or with the connection where y the airis transferred from the low to the high pressure stage, or even-with theinlet 6, provided such connection be between the throttle fand the pump.In the latter event a. partial vacuum would exist below the piston m,and the spring p would be adapted.

to act against the pressure of the atmos phere at the other sidethereof. I

In order to permit the passage of a desired or predetermined minimumamount of air so as to insure a pressure of low value in the injectionline appropriate. for a certain light load or for no load, a by-pass. gis. provided around the valve member '1: and its seat, this by-passbeing of small cross-sectional area or having its area' reduced'by anadjusting valve 7-. Such valve enables the minimum flow and minimumpressure of the injection air to be set for any value desired.

In operation, if there. is a change in the working load of the engine,the overnor 9 moves the valve f in the intake 0% the pump in theappropriate manner to increase or decrease the amount of air drawn in,as the case may be, and the resulting change in pressure in the lowerpressure stages or passages of the moves the valve member a in theinjection hne, so as to increase or decrease the area pump iscommunicatedpromptly to the pneumaticdevice m, which for flow, therebyproducing an increase or decrease in the pressure in the line leading tothe fuel valve.

' With multicylinderv motors there may be devices Z, m for each cylinderor group of cylinders, or an assemblage such as shown may serve all ofthe cylinders. Manifestly numerouschan es and substitutions may be madewithout eparting from the invention,

as, for example, a diaphragm device could be used in place of thecylinder and'piston construction mi What is claimed as new is 1. Thecombination with an internal combustion engine having fuel injectionmeans, an air compressor, a high pressure line connecting the compressorwith said fuel injection means, and a governor controlling the aircompressor, of a throttle valve in the high pressure line comprising acasing and valve seatand a valvemember movable to-' tion of theeompressor and controlling said valve.

3. The combination with an internal combustion engine of the Diesel typehaving fuel injection means and a high pressure line leading thereto, ofa flow-controlling valve in said line, and a by-pass around said valveadapted to permit the passage of a limited quantity of air.

.4. The combination with an internal com bustion engine of. the'Dieseltype having fuel injection means. and a high pressure line leadingthereto, of a. flow-controlling I ineaeei valve in said line, a lay-passaround said valve, and a flow-controlling valye in said by-pass forpermitting the passage of an adjustable minimum quantity of air.

5 5. The combination with an internal combustion engine of the Dieseltype having fuel injection means and a high pressure line leadingthereto, of automatic means for regulating the flow and consequently the10 pressure in said line, and a by-pass around said means adapted topermit a predetermined minimum flew.

In testimony whereof, I have signed this specification in the presenceof two witnesses.

JAKQB MULLER Witnesses CARL Gnennn, HARRY A. MCBRIDE.

